arch/kmap: remove BUG_ON()

Patch series "Remove duplicated kmap code", v3.

The kmap infrastructure has been copied almost verbatim to every
architecture.  This series consolidates obvious duplicated code by
defining core functions which call into the architectures only when
needed.

Some of the k[un]map_atomic() implementations have some similarities but
the similarities were not sufficient to warrant further changes.

In addition we remove a duplicate implementation of kmap() in DRM.

This patch (of 15):

Replace the use of BUG_ON(in_interrupt()) in the kmap() and kunmap() in
favor of might_sleep().

Besides the benefits of might_sleep(), this normalizes the implementations
such that they can be made generic in subsequent patches.

Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christian König <christian.koenig@amd.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Link: http://lkml.kernel.org/r/20200507150004.1423069-1-ira.weiny@intel.com
Link: http://lkml.kernel.org/r/20200507150004.1423069-2-ira.weiny@intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/arch/arc/include/asm/highmem.h b/arch/arc/include/asm/highmem.h
index 1af00ac..042e929 100644 (file)
--- a/arch/arc/include/asm/highmem.h
+++ b/arch/arc/include/asm/highmem.h
@@ -45,7 +45,7 @@ static inline void flush_cache_kmaps(void)
 
 static inline void kunmap(struct page *page)
 {
-       BUG_ON(in_interrupt());
+       might_sleep();
        if (!PageHighMem(page))
                return;
        kunmap_high(page);

diff --git a/arch/arc/mm/highmem.c b/arch/arc/mm/highmem.c
index fc8849e..39ef7b9 100644 (file)
--- a/arch/arc/mm/highmem.c
+++ b/arch/arc/mm/highmem.c
@@ -51,7 +51,7 @@ static pte_t * fixmap_page_table;
 
 void *kmap(struct page *page)
 {
-       BUG_ON(in_interrupt());
+       might_sleep();
        if (!PageHighMem(page))
                return page_address(page);
 

diff --git a/arch/arm/mm/highmem.c b/arch/arm/mm/highmem.c
index a76f8ac..cc6eb79 100644 (file)
--- a/arch/arm/mm/highmem.c
+++ b/arch/arm/mm/highmem.c
@@ -42,7 +42,7 @@ EXPORT_SYMBOL(kmap);
 
 void kunmap(struct page *page)
 {
-       BUG_ON(in_interrupt());
+       might_sleep();
        if (!PageHighMem(page))
                return;
        kunmap_high(page);

diff --git a/arch/csky/mm/highmem.c b/arch/csky/mm/highmem.c
index 8131291..690d678 100644 (file)
--- a/arch/csky/mm/highmem.c
+++ b/arch/csky/mm/highmem.c
@@ -29,7 +29,7 @@ EXPORT_SYMBOL(kmap);
 
 void kunmap(struct page *page)
 {
-       BUG_ON(in_interrupt());
+       might_sleep();
        if (!PageHighMem(page))
                return;
        kunmap_high(page);

diff --git a/arch/microblaze/include/asm/highmem.h b/arch/microblaze/include/asm/highmem.h
index 332c78e..99ced72 100644 (file)
--- a/arch/microblaze/include/asm/highmem.h
+++ b/arch/microblaze/include/asm/highmem.h
@@ -66,7 +66,7 @@ static inline void *kmap(struct page *page)
 
 static inline void kunmap(struct page *page)
 {
-       BUG_ON(in_interrupt());
+       might_sleep();
        if (!PageHighMem(page))
                return;
        kunmap_high(page);

diff --git a/arch/mips/mm/highmem.c b/arch/mips/mm/highmem.c
index d08e6d7..edd889f 100644 (file)
--- a/arch/mips/mm/highmem.c
+++ b/arch/mips/mm/highmem.c
@@ -28,7 +28,7 @@ EXPORT_SYMBOL(kmap);
 
 void kunmap(struct page *page)
 {
-       BUG_ON(in_interrupt());
+       might_sleep();
        if (!PageHighMem(page))
                return;
        kunmap_high(page);

diff --git a/arch/nds32/mm/highmem.c b/arch/nds32/mm/highmem.c
index 022779a..4c7c28e 100644 (file)
--- a/arch/nds32/mm/highmem.c
+++ b/arch/nds32/mm/highmem.c
@@ -24,7 +24,7 @@ EXPORT_SYMBOL(kmap);
 
 void kunmap(struct page *page)
 {
-       BUG_ON(in_interrupt());
+       might_sleep();
        if (!PageHighMem(page))
                return;
        kunmap_high(page);

diff --git a/arch/powerpc/include/asm/highmem.h b/arch/powerpc/include/asm/highmem.h
index a4b65b1..529512f 100644 (file)
--- a/arch/powerpc/include/asm/highmem.h
+++ b/arch/powerpc/include/asm/highmem.h
@@ -74,7 +74,7 @@ static inline void *kmap(struct page *page)
 
 static inline void kunmap(struct page *page)
 {
-       BUG_ON(in_interrupt());
+       might_sleep();
        if (!PageHighMem(page))
                return;
        kunmap_high(page);

diff --git a/arch/sparc/include/asm/highmem.h b/arch/sparc/include/asm/highmem.h
index 18d7769..7dd2d4b 100644 (file)
--- a/arch/sparc/include/asm/highmem.h
+++ b/arch/sparc/include/asm/highmem.h
@@ -55,7 +55,7 @@ void kunmap_high(struct page *page);
 
 static inline void *kmap(struct page *page)
 {
-       BUG_ON(in_interrupt());
+       might_sleep();
        if (!PageHighMem(page))
                return page_address(page);
        return kmap_high(page);
@@ -63,7 +63,7 @@ static inline void *kmap(struct page *page)
 
 static inline void kunmap(struct page *page)
 {
-       BUG_ON(in_interrupt());
+       might_sleep();
        if (!PageHighMem(page))
                return;
        kunmap_high(page);

diff --git a/arch/x86/mm/highmem_32.c b/arch/x86/mm/highmem_32.c
index 0a1898b..8af6638 100644 (file)
--- a/arch/x86/mm/highmem_32.c
+++ b/arch/x86/mm/highmem_32.c
@@ -15,8 +15,7 @@ EXPORT_SYMBOL(kmap);
 
 void kunmap(struct page *page)
 {
-       if (in_interrupt())
-               BUG();
+       might_sleep();
        if (!PageHighMem(page))
                return;
        kunmap_high(page);

diff --git a/arch/xtensa/include/asm/highmem.h b/arch/xtensa/include/asm/highmem.h
index 04e9340..413848c 100644 (file)
--- a/arch/xtensa/include/asm/highmem.h
+++ b/arch/xtensa/include/asm/highmem.h
@@ -73,7 +73,7 @@ static inline void *kmap(struct page *page)
         */
        BUILD_BUG_ON(PKMAP_BASE <
                     TLBTEMP_BASE_1 + TLBTEMP_SIZE);
-       BUG_ON(in_interrupt());
+       might_sleep();
        if (!PageHighMem(page))
                return page_address(page);
        return kmap_high(page);
@@ -81,7 +81,7 @@ static inline void *kmap(struct page *page)
 
 static inline void kunmap(struct page *page)
 {
-       BUG_ON(in_interrupt());
+       might_sleep();
        if (!PageHighMem(page))
                return;
        kunmap_high(page);